It seems once the front has passed through thats when we will start see the cold upper air temps.Issued by MetService at 04:25 pm Tuesday 05 July 2011
Valid until 05:00 am Wednesday 06 July 2011
This watch affects people in the following weather forecast districts:
Northland
Auckland
Great Barrier Island
Coromandel Peninsula
Waikato
Waitomo
Taumarunui
Taranaki
An active front is expected to move onto the west of the North Island late this evening i.e. Northland and Taranaki by about midnight, and then move quickly eastwards to lie east of the Coromandel Peninsula by 7am Wednesday morning. Squally thunderstorms are expected along the front. Some of these thunderstorms may become SEVERE and have the potential to produce local wind gusts of 120km/hr or more. In addition, there is a risk that one or two of these thunderstorms could produce a tornado, especially in coastal areas.
Wind gusts of this strength can cause some structural damage, including trees and power lines, and may make driving hazardous. If any tornadoes occur, they will affect very localised areas only.
Here is the 3 AM 500MB Temp and SFC B4LLI chart when the front is expected to hit.